12 Beauty Lessons We've Learned From Celebrity Sisters

Having a sister means stealing each other's clothes and fighting over the bathroom mirror. It also means enjoying two wardrobes and sharing new beauty-product tips and tricks. Here, our five favorite sets of celebrity sisters and the beauty lessons we've learned from them.

ELIZABETH OLSEN

A little lash definition makes all the difference.

Elizabeth proves that it is possible to have long, full lashes that don't look clumpy or spidery—without adding falsies. For thick, extension-length fringe that emphasizes your eyes and gives you that eight-hours-of-sleep look, "you want to use a mascara that's both lengthening and volume-building," says makeup artist Diane Kendal. "The thick formula will give fullness at the base, and the wand will separate lashes for a longer look." Our current favorite: Revlon Lash Potion by Grow Luscious Volume & Length Mascara.